Utility carts, sometimes referred to as janitorial carts, are wheeled carts typically used by maintenance personnel to carry buckets, cleaning tools, cleaning chemicals and the like as they proceed with their cleaning rounds. Such carts often have a cabinet mounted on a wheeled base, with a lockable door which provides access to chemicals and tools kept inside the cabinet. Some include a “lock box” mounted on top of the cabinet which can similarly be used.
Particularly in hospital settings, it is important that cleaning chemicals and dangerous tools be kept locked up at all times, except when the maintenance person needs access to them. In such environments, it is often by regulation that the door or box must at all times be locked. Thus when a cleaning person enters a room to clean, he or she opens the box or cabinet to gain access to chemicals or tools needed for cleaning, but then must lock the door or box again while he or she is attending to the cleaning work. Often, the cleaning or maintenance person must unlock, open, close and re-lock the cabinet door or lock box several times during the ten or fifteen minutes he or she is in a room cleaning it.
U.S. Pat. No. 5,485,733 is exemplary of magnet latches which have been used to lock cabinet doors. Three magnets are employed in the locking system. A rotating latch comprises a magnet, and a separate “biasing” magnet is located nearby. The like poles of the two magnets are positioned adjacent one another, such that the rotating latch is biased into engagement with a catch, which prevents one from opening the cabinet door. A separate magnetic key is fitted with a third magnet, powerful enough to overcome the repulsion of the biasing magnet relative to the rotating latch. When the opposite pole more powerful key magnet is placed near the outside of the cabinet door, in the vicinity of the latch, it causes the latch to rotate to its open position, allowing the door to be opened. When the door is closed, the like pole of the biasing magnet causes the latch to rotate back into its locking position.